filling ac

can anyone tell me how to get my compressor to kick on so i can get some refridgerant ito it. years ago you used to be able to jump the plug that plugs into the accumulater where the low freon switch was and the compressor would kick on and suck the freon out of the can into the system, is that still possible because i am not getting any juice to the comp. so i cant get any juice in.
dont tell me take it to a shop, because thats the last thing i want to do untill i am sure it will take a charge and hold it. right now i have no cold air at all, anywhere, front or back.
this is my 94 suburban with duel air and it says it takes the new 134 refridgerant.

can anyone tell me how to get my compressor to kick on so i can get some refridgerant ito it. years ago you used to be able to jump the plug that plugs into the accumulater where the low freon switch was and the compressor would kick on and suck the freon out of the can into the system, is that still possible because i am not getting any juice to the comp. so i cant get any juice in.
dont tell me take it to a shop, because thats the last thing i want to do untill i am sure it will take a charge and hold it. right now i have no cold air at all, anywhere, front or back.
this is my 94 suburban with duel air and it says it takes the new 134 refridgerant.

You must first put a vacuum pump on the system, It will pull 20" or so then Turn the pump off and let the system stand for about 20 minutes, If the vacuum rises there is a leak and a leak detector is the easiest way to locate it.
If you pull the system down to the proper vacuum, The vacuum will suck the 134 into the system without trying to jump anything.
Non use of a vacuum pump and jumping the low pressure switch is not a proper way to try to charge a system and it will not cool properly even if you do get it charged.

ok, when you put the system into a vacum it just sucks the moisture out of the system. After it holds vacum you either have to use a tank warmer which i don't suggest or the best method is to start putting the refrigerant in then start the vehicle and put the system to max a/c, if anyone has any more ?'s just ask, i know refrigeration systems

ok, when you put the system into a vacum it just sucks the moisture out of the system. After it holds vacum you either have to use a tank warmer which i don't suggest or the best method is to start putting the refrigerant in then start the vehicle and put the system to max a/c, if anyone has any more ?'s just ask, i know refrigeration systems


I know refrigeration systems also !!!

The vacuum will draw in the refrig. and get the process started. The compressor will start running in short spurts, enough to get the low side pressure down. As you fill the system the compressor will run more.